Transmembrane Emp24 Domain-Containing Protein 9 (TMED9) Antibody

Background

TMED9 is a critical member of the p24 protein family that regulates protein trafficking between the endoplasmic reticulum (ER), ER-Golgi intermediate compartment (ERGIC), and the Golgi apparatus. It functions as a cargo receptor, facilitating the export of correctly folded proteins through COPII-coated vesicles and supporting retrograde retrieval via COPI transport machinery. TMED9 also regulates protein quality control, ensuring proper sorting, maturation, and recycling of secretory and membrane-bound proteins. It plays additional roles in signaling pathways, including Wnt and growth factor signaling, by modulating receptor trafficking and localization at the plasma membrane. TMED9 is widely expressed, particularly in secretory cells, immune tissues, and proliferative compartments. Dysregulation of TMED9 has been associated with cancers and metabolic diseases, where altered trafficking dynamics impair protein secretion and receptor signaling. Knockdown studies reveal defects in vesicle formation, impaired Golgi organization, and disrupted cellular homeostasis, emphasizing its essential role in coordinating vesicular transport, protein quality control, and signaling regulation.